Myofibril - these are cylindrical structures that run lengthwise through the muscle cell and are made of two (2) smaller structures: 1.) thin myofilaments - actin protein 2.) thick myofilaments - myosin protein
Sarcolemma - the outer surface of a muscle cell
Sarcolplasmic Reticulum - a network of tubes running the length of the cell (looks like smooth endoplasmic reticulum). Inside this structure calcium ions, Ca2+, are stored, which are used to produce muscle contractions.
1.) thin myofilaments - actin protein
2.) thick myofilaments - myosin protein
Sarcolemma - the outer surface of a muscle cell
Sarcolplasmic Reticulum - a network of tubes running the length of the cell (looks like smooth endoplasmic reticulum). Inside this structure calcium ions, Ca2+, are stored, which are used to produce muscle contractions.
http://www.clt.astate.edu/mhuss/Chapter%209%20-%20Muscular%20System_files/frame.htm#slide0005.htm
Sarcomere - these are the functional units of the muscle. There can be up to 100,000 of these in one myofibril.
Z-disc - these are zones that seperate sarcomeres
A-band - a dark area in a sarcomere made up mostly of thick myofilaments (myosin)
I-band - a lighter colored area of the sarcomere that is only composed of thin myofilament (actin).
H-zone - the center area of the A-band that only contains thick myofilaments (myosin), no thin (actin).
http://www.websters-online-dictionary.org/definitions/Sarcomere?cx=partner-pub-0939450753529744%3Av0qd01-tdlq&cof=FORID%3A9&ie=UTF-8&q=Sarcomere&sa=Search#922